When we are presented with information, the Spirit of God inside of us does not sit back and say "you figure out if that is truth or a lie". The Spirit of God tells us if what we hear/see is true or false. The Spirit of God in us will NEVER tell us something is true if there is anything false to it.
Absolutely.
BUt, does everyone hear what the Spirit says with clarity?
And does everyone ever get confused between the voice of the Spirit and his own internal voice?
The spirit does no operate us like puppets.
We must not be fooled into thinking that as born from above believers - who have the very Spirit of God living in us, who is leading us each and every day to the eternal kingdom of God - that we will not know what is true and what is false.
Good advice.
But people are fooled all the time.
That's what confession is for.
Under the authority of the Lord Jesus the Christ, I can say before you that the truth can be known - the truth should be known - God has no pleasure in those who shrink back in doubt. Listen, when God speaks truth to us, He wants us to receive it and know it.
Unfortunately, there's a lot of interference; our own internal voice, the demands of the flesh (which is dead but won't lie down) the deceit of the Devil, the influence of friends and family, etc.
That's why the practice of the virtues is important.
That's why daily prayer is important.
That's why daily scripture reading is important.
The more familiar one is with the truth, the easier it is to identify the false.
If it were as easy as just listening to the Spirit then no Christian would ever sin and none of the warnings, admonitions and encouragement to persevere in doing righteousness would have been necessary to have been put in the scriptures.
But the Holy Spirit, who leads us into all truth, had the writers of the scriptures put them there because He knew we would need them.